Monitoring save code now for type svn report error [1]
from the worker stacktrace, this looks like an off by one when starting up visits from
an already visited repository:
```
Apr 17 17:07:24 worker2 python3[2637389]: [2021-04-17 17:07:24,952: INFO/ForkPoolWorker-1] Load origin 'https://github.com/cran/SCRABBLE' with type 'svn'
Apr 17 17:07:26 worker2 python3[2637389]: [2021-04-17 17:07:26,765: ERROR/ForkPoolWorker-1] Loading failure, updating to `failed` status
Traceback (most recent call last):
File "/usr/lib/python3/dist-packages/swh/loader/core/loader.py", line 330, in load
self.prepare()
File "/usr/lib/python3/dist-packages/swh/loader/svn/loader.py", line 756, in prepare
dump_path = self.dump_svn_revisions(self.svn_url, last_loaded_svn_rev)
File "/usr/lib/python3/dist-packages/swh/loader/svn/loader.py", line 741, in dump_svn_revisions
% (last_dumped_rev, last_loaded_svn_rev)
Exception: Last dumped subversion revision (0) is lesser than the last one loaded into the archive (0).
```
(which kinda reminds me that I wanted to simplify the complexity in that instanciation
loader and align it with other loaders...)
This needs some fixing.
[1] Ui view
```
Exception: Last dumped subversion revision (0) is lesser than the last one loaded into the archive (0).
```